1. Field of the Invention
The present invention relates to a package tester for electric parts, electronic parts, etc., sequentially formed on a continuous tape and called a tape carrier package (TCP). The test occurs by applying an electric current through this package and transmitting signals, etc., to the package. The present invention also relates to a package tester for determining whether the package is good or bad in quality, and screening the package on the basis of the quality determinatior, etc.
2. Description of the Related Art
A package of electric parts, electronic parts, etc. (such as an IC package) can be individually formed as a unit. However, such a package can also be provided as a tape carrier package (TCP). This TCP is also called a TAB package and is normally formed on an elongated film made of synthetic resin. A package tape carries many packages and generally has several ten meters in length. The length of package tapes are expected to increase in the future.
The package tape normally has perforations in lug portions thereof. The perforations are used to feed and position the tape and are spaced from each other at a predetermined distance. Such a package tape is wound around a reel, etc. Each of the packages is tested by flowing an electric current therethrough and transmitting signals, etc. to each of the packages. In this package test, each of the packages is mounted onto a package socket.
When the package tape is cut in the shape of stripes to test a package, the cut package tape must be again connected to a series of package tapes (in many cases after the package test) so as to continuously feed the package tape to a next process. Such a connecting operation is troublesome. Further, no initial accuracy in each of positions of a lug hole, an electrode of each of the packages, etc. can be obtained with respect to the series of connected package tapes so that it is difficult to smoothly feed and position the package tapes in the next process. An area for sticking and connecting the package tapes to each other must be secured on the package tapes. Therefore, no packages at both ends of the cut package tape can be used so that yield of the packages is reduced.
It is also impossible to test a large amount of packages for a limited time in the above method in which the packages are sequentially tested one by one on the package tape without cutting the package tape.
Japanese Patent Application Laying Open (KOKAI) No. 2-275376 shows one method for solving such problems. In this method, package sockets are arranged in a spiral shape on a cylindrical supporting body. A package tape is continuously connected to this package socket line without cutting the package tape. However, in this method, the package tape is twisted so that the package tape and packages are damaged and reliability of the package test is reduced.